i was just chatting with my local speed freak mechanic to do a SOHC piston swap. He looks at the parts i have and says... ok. you got the pistons, rings and circlips, but where are your rod bearings? ...am i missing a part from my "kit" or does this guy talk more than he should? This f**kin a**hole wont leave me alone saying "why dont you go turbo or get a supercharger it would cost less and you can really drive your car to the ground" if i wanted a f**kin turbo id ask about a turbo jerk also "your engine cant take more than 4 medium-hard runs and one HARD run with high compression". What a piece of crap that fool is. he was also like "those ecu upgrades for high compression are gonna retard your timing" and i have no freaking clue because JWT wont tell me sh*t about "how" they do it. :angryfire

hmm...i just noticed your sig.

the 9.1:1 SOHC pistons along with a thinner head gasket will put you at or above 12:1 compression. is this going to be a daily driver?

9.1:1 SOHC pistons will give you an 11.6:1 ratio with a stock head gasket. The pistons from a 90 SOHC, which are 8.6:1, will make it 11.1:1. I wouldnt get a thin head gasket either. You need to be able to drive it on pump gas and 11.1:1 is about the heighest you could go and do that. 12:1 compression would give you big knock unless you are using race gas.

As for your rod bearings, if you are tearing it all apart, you want to replace those. Are you reusing you DE rods or trying to use the rods off the SOHC? I belive the rods are identical. Either way, now is a good time to replace the rod bearings. If you are not replaceing the rod bearings, then yours 'should' still be on the large hole end of the rod. There are 2 per rod, 1 for each half of the circle that goes around the crank.

I'd have to agree with that mechanic guy somewhat. Adding the SOHC pistons to give you higher compression will in the long run, give you more trouble than its worth. Why not spend that time and labor and invest in a good set of pistons and rods and prep the interior for turbo? That's what I would do... And yes, your missing the rod bearings. You should also have a gasket kit to replace all the old gaskets.

okay im a bit cooled off now. i really wanted to know if that ecu upgrade just retards your timing or what? also if i do go high compression, how is the motor going to take it? will i have less luck with that then turbo in terms of making the motor last? You know i chose high compression route cause i didnt want to have to wait for a turbo to spool up for performance, and im a big fan of how ka's act under high compression. so i got the money, i just need some advice.

well since you already got the pistons/rings and clips, I would go buy the rod bearings and drop those in your engine along with new gaskets, but I would also get my ecu retuned by jwt to extract all the power the engine can push out. And as for the turboed engine, well if you drive responsibly it'll last.

so what exactly does the ecu change to get all that power? that guy said it retards the timing and im not sure i want that...